As those skilled in the art of combustion turbines are aware, the maximum power output of a gas turbine is achieved by heating the gas flowing through the combustion section to as high a temperature as is feasible. The hot gas, however, heats the various turbine components, such as transitions, vane segments, ring segments, and blades, that it passes when flowing through the turbine. Such components are critical components because their failure has direct impact on the operation and efficiency of the turbine.
Accordingly, the ability to increase the combustion firing temperature is limited by the ability of the critical components to withstand increased temperatures. Consequently, monitoring the state of the hot gas flowing through the turbine and the critical components themselves is essential to determine the state of the turbine's critical components as well as to determine the efficiency of the turbine.
The harsh environmental conditions inside the turbine, however, makes measurement of these conditions and components rather difficult. Many sensors are limited to operating below certain temperatures, can only function in stable environments, or can only operate for short periods of time in severe conditions. Consequently, the difficulty in accurately monitoring critical components of a gas turbine leads to inefficient turbine operation and significant downtime for off-line inspection of components. It is, therefore, desirable to provide an apparatus that can be used to protect sensors in the harsh environment of gas turbines so that the sensors can operate effectively.